I hoping that someone out there might have a solution to a strange issue that popped up yesterday on my 2003 Mini Cooper.

The car is actually my sisters car and is only driven a few times per year when she's home from Hawaii visiting the east coast. The car had been sitting for approximately 4 months (inside a garage) and when I went to start it the battery was completely dead (dome light didn't even come on). When I attempted to jump start the car, the only thing I got was a second or 2 of clicking from the starter and that was it. With the battery being the original, I went to Sears and picked up a replacement and proceeded to install it.

The car instantly started right up and everything appeared to be good to go. After the car was running for around a minute a loud buzzing started coming from the stereo speakers which was completely turned off. If I turn on the radio (which is the stock single disk unit) I could barely hear the radio over the buzzing sound. So that it's bearable to even drive the car, I've pulled both radio fuses. I did try switching out the battery with a new one of a different brand to no avail. The radio had previously been working flawlessly since the car was purchased back in 2003.

Does anyone happen to have any insight as to where the sound/ interference could be coming from? One interesting thing I've noticed is that when you hit the horn button the pitch of the whine changes tone - almost like the sound is coming from a grounding issue.

 

I would guess your speaker diaphams have split. You can check by removing the door panel and looking.
Both ours, and our son's, '03's have had to have our front speakers replaced. Rear speakers still sound good.
It is a pretty easy DIY project.

 

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